Dyeing animal fibers



wherein Riis an alkylfradicle. X1 and X2 are Patented May 21, 1935 UNITED l S i TE T OFFICE DYEING ANIMAL FIBERS I Heinrich Wagner, Hans Krzikalla, and: Alfred. Kirsch, Mannheim, Germany,-, assignorsxto general Aniline Works, Inc., New YorkyN. Y., a corporation of Delaware No Drawing. Application July 19, 1933, Serial;

No. 681,216. In Germany July 26, l932 v r v 10 Claims. ."Thepre'sent invention'relates to a process of dyeing animal fibers such as skins, hairs, feathers and leather. V a

We have foundthat very fast dyeings on animal fibrous materials such as skins, hairs, feathers and leather, are obtainedby treating them with iolutmns of compounds having the general strucure hydrogen atoms or membersof a benzene nucleus, n' the presence of oxidizingagents; Compounds of the kind inquestion are l'. l'-naphthohydroquinone monoalkyl'ethe'rs', l-hydroxy-i alkOXyan- 'thracenes, and their substitution products; as for example their halogen substitution products. Generally speaking intense blue to green dyeings are obtained on animal fibers by means of the said compounds.

The 1-hydroxy-4-alkoxyanthracenes are obtainable by partial alkylation of 1.4-dihydroxyanthraeenes which is attained by treating the said initialmaterials under mild alkylationconditions, for exampleby stirring them in the cold for a short time with asolution oihydrochloric acid in the alcohol to beused for etherification. Halogenated derivatives may be obtained by partial alkylation of initial materials containing halogen; for example halogenated 1-hydroxy-4-alkoxyanthracenes can'be prepared by partial alkylation of 1. l-dihydroxyanthracenes which are halogenated in the. 5-, 6-, '7- or 8-} position; the latter compounds maybe obtained-by reduction of the corresponding quinones.

,In order totvary the shades of color other readily oxidizab1e aromatic compounds containing amino or'hydroxyl groups usual-for thedyeing ofanimal fibers may be added to the solutionsoi the compounds defined above, as for example para-diaminobenzene, para-aminophenol, orthoaminophenol or alpha-naphthol.

If desired, mordants, as for example iron, copper, chromium-z or othermetal compounds may be employed for mordanting the fibrous materials. In this casesomeiinfiuence on the depth and shade of color of the dyeings may be exerted.

. The treatment may be carried out in a neutral or weakly acid medium. 1 It is, however, preierable (c1. 8- 5 n n r to proceed bytreating the material to ibe dyed with a weakly alkaline solution of a hydroxyalkoxy compound as defined above, the oxidizing agent being added to the solution or causedto react before; during or after the introduction. of? the goods. The treatment with oxidizing agents may also be effected in a separate operation. The desired dyeing may. be obtained by hanging. the skins. or the like impregnated Witha 1.4'-.-naphthohydroquinonermonalkyl ether or thelike the] air, as is usual inc'the development of: vatzdyeings. The alkalinity of the caustic soda solutionof the l .4 -naphthohydroquinone; monalkyli ether or." the. like may be wholly or partially. destroyedrby the addition of acids or acid salts or altered by the addition of ammonium salts or ammonia derivatives before or, duringthedyeing; Asa'very suitable oxidizing agent may bementioned in partic.- ular hydrogen peroxide, but other. oxidizing agents, as for. example nitrites;peroxidessuch as sodium peroxide" and'bariumi peroxide, chromates;

persulphates. andz-perborates. may also. be. employed. a v Several: of the: compounds as" defined above may be;used;:.togetherfor the dyeing process, for examplezmix-tures ofth'naphthalene andLanthrae cenederivatives may be employed; 'IheL-addition of emulsifying. agentssuchas oleylsulphonate, sulphite: waste liquor; and alkylatedinapha thalene sulphonic acids; to: the: dye-bath is .very advantageous in many cases; i

The dyestuffs formed on: the fiber: are most probably compounds 01117119131382 'wherein R stands for analkyl radicle and wherebichromate, are immediately introduced. The dyeing is carried out at room temperature for several hours, very strong reddish blue shades being obtained. Pale to dark blue dyeings are obtained depending on the nature of the mordant. If copper compounds are employed as mordants somewhat less strong greenish blue shades are obtained. If iron mordants are used, a dyeing of dull greenish blue shades somewhat less strong than those obtained with chromium mordants,

is produced. It is advantageous to effect the aforesaid process with the addition 'of 0.3 kilogram of an alkylated naphthalene sulphonic acid or 0.1 kilogram of oleylsulphonate or 0.3 kilogram of a sulphite waste liquor containing 20 per cent of active substance.

Example 2 0.6kilogram of 1.4-naphthohydroquinone monomethyl ether is dissolved in 6 litres of normal caustic soda solution and added to a solution of kilograms of para-diaminobenzene in 100 litres of Water. '6 litres of 30 per cent hydrogen peroxide are also added and the goods, as for example skins, are dyed for several hours at room temperature. When employing a skin which has been mordanted with a salt ofrhexavalent chromium, the hairis dyed a deep black shade and the leather a blue shade. When employing instead of the abovementioned methyl other the corresponding ethyl or amyl compounds, dyeings of very similar shades are obtained. If leather .be' used insteadof a skin similar dyeings are produced.

icEzcample 3 0.6 kilogram of lA-naphthohydroquinone monomethyl ether is dissolved in 6 litres of normal caustic soda solution and diluted with water to form 100 litres of-liquor; After adding litres of 3 per cent hydrogenperoxide to the dye-bath the goods to be dyed, for example chromemordanted skins, are introduced at once. The dyeing is carried out for several hours at room temperature whereby dark-blue shades are obtained on the hairs and the leather of the skins. As soon as the dyeing is'finished the skins are removed from the bath and, if desired, rinsed for ashort time. 'Then the skins are introduced While still wet into a dye-bath containing for example 5 kilograms of para-diaminobenzene, dissolvedin 100 litres of water and 6 litres of 30 per cent hydrogenqperoxide. 1' Deep black shades are obtained on the-hairs and blue shades on the leather. Before being introduced into the second dye-bath mentioned the skins may be treated once more with a metal mordant.

Example 4 0.6 kilogram of 1-hydroxy-4-methoxyor ethoxy-anthracene is dissolved in about 6 litres of normal caustic sodasolution and diluted with water to form 100 litres of liquor. After adding 10 litres of 3 per cent hydrogen peroxide, the goodsto be dyed, as for example mordanted skins, are immediately introduced into the liquor. Dyeing is carried on for several hours at room temperature, olive green dyeings being obtained.

Other oxidizing agents, as forexample nitrites, peroxides, 'chromates, persulphates or perborates, may be employed instead of hydrogen peroxide.

Furthermore combination dyeings may be pre: pared with other oxidizable compounds containingiamino or hydroxy groups, as for example para-diaminobenzene, paraor ortho-aminophe- 1101 or alpha-naphthol. Displacements in the shade of color may be effected by employing different metallic mordants, as for example iron, copper or chromium compounds.

Instead of 1-hydroxy-alkoxyanthracenes, de- I rivatives thereof, as for example halogenated products, which are capable of being oxidized, may be employed for dyeing.

I What we claim is:-

1. The process of dyeing animal fibers, which comprises treating the said fibers with a solution of a compound having the general structure 0H V V wherein R is an alkyl radicle, X1 and X2 are hydrogen atoms or members of a benzene ring, in the presence of an oxidizing agent.

2. The process of dyeing animal fibers, which comprises treating the saidfibers with an alkaline solution of a compound having the general structure wherein R is an alkyl radicle, X1 and X2 are hydrogen atoms or members of a benzene ring, in the presence of an oxidizing agent.

3. The process of dyeing animal fibers, which comprises treating the said fibers with an alkaline solution of a compound having the general structure 7 4. Animal fibers dyed with compounds having probably the general structure II II X I x, 7

OR OR wherein R is an alkyl radicle and wherein X1 and X2 are hydrogen atoms or members of a benzene ring.

5. Animal fibers dyed with compounds corresponding probably to the formula 0 o n r OR OR wherein R stands for an alkyl radicle.

.CH: LCH

sponding probably to the formula wherein R. stands for an alkyl radicle.

8. Animal fibers dyed with compounds corresponding probably to .the formula 7. Animal fibers dyed with compounds corre-' 9. The process of dyeing animal fibers which comprises treating the said fibers with a solution of a compound having the general structure wherein X1 and X: are hydrogen atoms or members of a benzene ring, inthe presence of an oxidizing agent.

10. Animal fibers dyed with compounds hav- 7 ing probably the general structure wherein X1 and X2 are hydrogen atoms or members of a benzene ring.

HEINRICH WAGNER. HANS KRZIKALLA. ALFRED KIRSCH. 

